1. Field of Invention
The present invention relates to a screen apparatus for projecting an image using an image projection device and a projector using the screen apparatus.
2. Description of Related Art
There are known projectors which display an enlarged image on a large screen. As one of the above projectors, a rear projection type projector projects an image from an image projection device to the rear side of a screen and the projected image is watched from the front surface side of the screen.
Since the rear projection type projector includes the image projection device and the screen in the cabinet of the apparatus, it is necessary to secure, in the cabinet of the apparatus, an optical distance between the image projection device and the screen in accordance with a display size of an image. Therefore, there is a problem that the rear projection type projector is generally large in size and a large space is necessary to install it. Further, there is also a problem that portability is not good.
The present invention provides a stand type screen apparatus that reduces the size of a rear projection type projector, decreases an installation space, and enhances portability.
Specifically, the invention provides a stand type screen apparatus for projecting an image on a screen using an image projection device that includes a base table, a projection device installing unit turnably mounted on the base table for detachably installing the image projection device, a support leg turnably mounted on the base table, and a screen holding unit holding the screen and turnably mounted on the support leg.
Since the stand type screen apparatus can be folded by turning the screen holding unit with respect to the support leg and turning the leg portion and the projection device installing unit with respect to the base table, respectively, the size of the apparatus can be reduced when it is not used. The reduction of the size of the apparatus when it is not used can decrease an installation space and enhance portability.
Note that it is preferable that the stand type screen apparatus can be folded to an approximate rectangular prism shape as a whole. When the shape of the stand type screen apparatus at the time it is folded is the approximate rectangular prism, the apparatus can be easily handled and further the portability thereof can be enhanced.
Further, it is preferable that casters are disposed on the vicinity of only one of the ends of the base table. With this arrangement, when the apparatus is moved, it can be easily moved by rotating the casters, whereby the portability can be more improved.
At the time, it is preferable that a grip portion is disposed in the vicinity of the end opposite to the casters, and the grip portion may be gripped and pulled when the apparatus is folded. In this case, the apparatus can be more easily moved by pulling the apparatus while gripping the grip portion.
Note that it is preferable that the support leg is extendable. With this arrangement, the size of the apparatus can be more reduced when it is not used.
Note that the projection device installing unit can be mounted in the vicinity of one of the ends of the base table, and the support leg can be mounted in the vicinity of the other end of the base table. With this arrangement, the projection device installing unit, the support leg and the screen holding unit can be effectively and compactly folded.
The base table can be provided with an accommodating unit for accommodating the projection device installing unit when the stand type screen apparatus is folded. With this arrangement, since the projecting device installing unit can be accommodated in the accommodating unit when the stand type screen apparatus is folded, the size of the apparatus can be more reduced when it is not used. Further, when the apparatus is used, an image supply device (computer, video equipment, and the like), and the like, which supplies image data to the image projection device can be accommodated in the accommodating unit when the apparatus is used.
Further, the base table also can be provided with a turnably disposed cover for covering the accommodating unit.
Note that the base table also may include a power supply unit having a power supply connecting terminal connected to an external power supply and a plurality of internal connecting terminals connected to the power supply connecting terminal in parallel therewith. The provision of the power supply unit permits power to be supplied to various kinds of electronic equipment, such as the image projection device mounted on the screen apparatus, the image supply device, and the like.
The projection device installing unit may include a speaker installing unit.
In the stand type screen apparatus it is preferable that the screen holding unit includes a mirror unit turnably mounted on the support leg and a screen unit turnably mounted on the mirror unit, and the light emitted from the image projecting device is projected to the screen after it is reflected from the mirror unit. With this arrangement, the light emitted from the image projection device can be reflected from the mirror unit and introduced to the screen unit.
At the time, it is preferable that the mutual positional relationship among the projecting device installing unit, the mirror unit and the screen is adjusted such that the image projected from the image projecting device installed to the projecting device installing unit is projected to approximately the center of the screen. With this arrangement, the image projected from the image projection device can be accurately projected on the screen.
Further, it is preferable that the screen unit is mounted in the vicinity of the upper end of the mirror unit on the lower side thereof and the mirror unit includes a shading unit in the vicinity of the upper end of the mirror unit for preventing external light from an upper direction from directly irradiating the surface of the screen on the mirror unit side.
With the above arrangement, since the leakage of the external light from the upper direction from the portion where the screen unit is mounted and the direct irradiation thereof on the surface of the screen on the mirror unit side can be suppressed, the deterioration of an image caused by the external light can be suppressed.
Note that a projector can be arranged by including the stand type screen apparatus and the image projection device for projecting an image.